Magneto-cut-off switch.



N. W. DALTON.

MAGNETO CUT-OFF SWITCH.

APPLICATION FILED NOV. 11. 19t6.

Patented Mar. 11, 1919 5110c v1 for NEL'50N W. DALTON.

WEE:

. lllll ATE NELSON W. DALTON, OF BUFFALO, NEW YORK, ASSIGNOR TO CURTISS AEROPLANE AND MOTOR, CORPORATION, A CORPORATION OF NEW YORK.

MAGNETO-CUT-OFF SWITGH.

Specification of Letters Patent.

Patented Mar. 11, 1919.

Application filed November 11, 1916. Serial No. 130,811.

To all whom it may concern:

Be it known that T, NELsoN W. DALTON, a citizen. of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Magneto-Cut-Off Switches, of which the following is a specification.

My invention relates in general to magneto switches and more particularly to the provision of a switch whereby the operation of dual magneto systems may be tested in aircraft motors.

Aeronautical motors are generally provided with a dual magneto system, one magneto, in a V-type motor, serving to supply each bank of cylinders. Should one of the magnetos become disabled the efficiency of the power plant is greatly decreased, and it immediately becomes necessary to ascertain which of the magnetos is inoperative. The means whereby this elimination test is accomplished is incorporated in the magneto cut-out switch mechanism, and hence replaces the more or less complicated magneto switch devices now in use. Moreover. by combining the additional features of my testing means, I simplify rather than complicate the switch structure which comprises a very small number of parts.

()f the drawings:

Figure 1 is an assembly view of the magneto cut-out switch;

Fig. :2 is a longitudinal sectional view;

Fig. 3 is a section on the line 3-3 of Fig. 2;

Fig. 4 is a section on the line 1-1 of Fig. 2; and

Fig. 5 is a diagrammatic view of the Wiring.

The main body or casing of the'switch, Wholly designated as 1, has laterally extending flanges 2 adapted to be bolted to a securing base (not shown). The curved portion of the body 1 is provided with a slot 3 designed to receive the switch handle 4 and its retaining leaf spring 5. The spring 5 serves to retain the switch lever 4 at positions of on and off by engaging a shoulder 6 formed adjacent the slot terminals. Within the housing lare a series of flanges 7 which serve as guides or spacers for insulating plates 7 and 8. The insulating plate 8 carries substantially at its center a screw threaded post 9. This post 9 serves as a pivot for the lever *1 and also as a ground wire terminal, as in Figs. 2 and 1 The plate 8 also carries on opposite sides of the post 9 a pair of wire terminals or posts 10 and 1.1 having leaf contacts as 12 adapted to engage the contact-portion of the switch arm 4: (see Fig. '2). These posts 10 and 11 are secured within holes. drilled in the plate 8, by means of suitable nuts and washers. The curved extent of the housing 1 is provided with three alined insulated openings as 13 through which the wires pass to the terminals 9, 10 and 11 above referred to. It may be seen that when the switch arm 4 is in the position of Fig. I 6., ofi'both magnetos will be grounded and therefore inoperative.

In order that the magnetos may be cut out independently of each other I provide a pair of push buttons 1% and 15 carried within sockets 16 formed in the grounded housing 1. The push buttons l-f and 15 are provided with coil springs 17 which normally hold said buttons extended. The entire housing 1 is grounded from the terminal post 9 by the switch arm '1' and spring 5 which make contact with the walls of the slot 3. The inner extremities of the push buttons 14 and 15 are provided with contact points or surfaces 18 which connect, when depressed, with the terminal posts 10 and 11, thereby grounding the terminals through the grounded switch casing.

The usual aeronautical motor is provided with two magnctos connected as in the wiring diagram, Fig. The high tension side L of one magneto is connected with one terminal 10 of the switch while the high tension terminal L of the other magneto is connected to the other terminal 11 of the switch. The center or blade terminal 9 is grounded as at 19. Throwing the switch to off position as indicated grounds the terminals LL of the magnetos. This grounds the high tension side of the magneto and thereby stops the supply of electricity to the plugs P and P. Movement of the switch-arm to on position completes the circuits of which the spark plugs PP form a part.

The operation of my device is as follows: Suppose one of the magnetos has become partially or totally disabled. It is then desired to ascertain which magneto is at fault. If, upon pressing the left button 15 the motor slows down or stops we know that the right hand magneto is the one at fault. Suppose, however, that neither of the magnet-0s are completely inoperative but that one of them is only partially disabled. Then by manipulating the push buttons separately and observing the motor operation as a result, the faulty or partially disabled. magneto may be quickly ascertained.

The constructional details of my invention are of great simplicity. The body portion 1 is preferably cast of some suitable metal and may be produced at slight cost. All the operating parts of the switch are carried upon the insulating plate 8 to which they are assembled before sliding it between its retaining flanges. The insulating plate 7 serves as a waterproof cover for the complete mechanism and is held in place by means of the cap 20 which closes the end of the housing. Bolts 20' function as fastening means for the casing 1 and as securing means for the cap 20. The bolts penetrate the flanges 2, the cap, and the securing base (not shown).

Althoughthe above specification sets forth the preferred embodiment of my invention, it shall be understood that interpretation of the invention should be made only in view of the claims.

I claim 1. The combination with a dual magneto system for explosion motors, of a magneto switch comprising opposed contacts, and a switch-arm movable into engagement with the respective contacts to simultaneously ground both magnetos.

2. The combination with a dual magneto system for explosion motors, of a magneto switch comprising devices independently operable to separately ground the magnetos.

3. The combination with amagneto switch for multiple magnetos, of ameans to simultaneou'sly ground the several magnetos, and

a means to ground the magnetos independently.

4. Thecom'bination with a dual magneto system for explosion motors, of a magneto system comprising means operable to simultaneously render both magnetos either operative or inoperative, and independent devices directly associated with said means to separately render either magneto inoper-- ative.

5. The combination with a dual'magneto system for explosion motors, of a magneto switch comprising opposed contacts, means movable into and out of engagement with the respective contacts to simultaneously render both magnetos either operative or inoperative, and devices independently cooperating with the respective contacts to render either magneto separately inoperative.

6. The combinationwith a dual magneto system for explosion motors, of a magneto switch comprising opposed contacts, means movable into and out of engagement with the respective contacts 'to simultaneously render both magnetos either operative or inoperative, and independent devices normally spaced from said contacts and independently movable into engagement therewith to separately render either magneto inoperative.

7. A switch for testing two'separate ignition circuits comprising two circuit terminals, a third terminal, means for simultaneously bridging andconnecting together all of said terminals, and separate push buttons for said circuit terminals adapted'to Connect them independently to said third terminal.

ously bridging and connecting together all of said terminals, and means for'separately and independently connecting said circuitterminals with said third terminal.

In testimony whereof I aflix my signature.

NELSON W. DALTON.

Copies of this patent may be obtained for five cents each, by addressing the Gommissioner of Patents,

Washington, D. G. 

